The subject matter disclosed herein relates generally to nuclear medicine (NM) imaging systems, and more particularly to NM imaging systems having a mechanism for stopping and/or removing a detector head.
In NM imaging, such as single photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging, radiopharmaceuticals are administered internally to a patient. The radiopharmaceuticals emit radiation that may be captured by an NM imaging system to generate images for diagnostic review. An NM imaging system may be configured as a multi-head system having a number of individual detector assemblies. The detector assemblies include a movable arm that extends radially-inward toward the patient and a detector head that is held by the movable arm. A positioning sub-system of the NM imaging system controls movement of the detector heads in order to acquire images of a designated region-of-interest. More specifically, the detector heads are positioned adjacent to the region-of-interest to detect the emitted radiation. The detector heads may be positioned within a few centimeters from the patient.
The patient is typically confined within a bore of the NM imaging system during the imaging session. After the imaging session, the patient may physically exit the bore or, in some cases, a table holding the patient may be directed out of the bore. Because the detector heads are positioned adjacent to the patient within the bore, it may be desirable to re-position the detector heads so that the patient can exit. The detector heads are typically moved by activating the same motors that position the detector heads relative to the patient for the imaging session. This standard mechanism for moving the detector heads may become unsuitable if, for example, a power failure occurs or the positioning sub-system malfunctions. In such instances, it may be difficult to remove the patient without injuring the patient or damaging the imaging system. Moreover, physically moving the detector heads away from the patient may be difficult or take a significant amount of time. The patient may become more uncomfortable or upset the longer the patient remains within the bore.